Problems in which a construction machine is stolen from a construction site have occurred frequently. A construction machine provided at a work site of a remote place is often left at the work site during work. Such a work site differs from a storage place of the construction machine monitored by an owner or a manager and theft prevention measures are insufficient and it becomes a situation in which theft tends to occur.
A theft prevention apparatus of an oil hydraulic construction machine is disclosed in JP-A-9-50584. In this theft prevention apparatus, when a predetermined personal identification number is entered at a key input device, a pilot oil hydraulic source is communicated with a pilot valve and an action of an oil hydraulic device is permitted. When the personal identification number is not inputted, the pilot oil hydraulic source and the pilot valve are shut off and the action of the oil hydraulic device is prohibited. There is also a description to the effect that the action of the oil hydraulic device is permitted by inserting an IC card instead of key input.
A theft prevention apparatus of an oil hydraulic construction machine is disclosed in JP-A-8-301072. In this theft prevention apparatus, when a predetermined personal identification number is not inputted from a key input device, even in the case of performing an engine starting operation, a starter circuit does not operate and starting of an engine is prohibited.
However, in the theft prevention apparatus of these construction machines, an operation different from normalcy of key input or insertion of the IC card every time the engine attempts to be started must be performed and its operation is troublesome. Also, in case of forgetting the personal identification number or forgetting to carry the IC card, the construction machine cannot be operated and there is also a disadvantage incapable of doing work.
On the other hand, a system for notifying a server of a management center for managing a construction machine of position information about said construction machine is disclosed in JP-A-2000-73411. According to this system, for example, an operating area of the construction machine is preset and a manager resident in the management center decides whether or not to deviate from the operating area based on position information sent from the construction machine to the management center through an artificial satellite. When the system decides that it deviates from the operating area, for example, it is configured so as to stop an engine by sending a signal for stopping an engine of the construction machine from the management center to the construction machine and breaking the passage of electric current through an engine starter motor and cutting fuel. The system acquires the position information about the construction machine all the time using a GPS (Global Positioning System).
In the management center side, by receiving this notification, occurrence of theft of the construction machine can know early and proper measures, for example, a report to the police or arrangements for an alternative machine, etc. can be taken speedily.
However, when the theft of the construction machine occurs, only sending of the position information to the management center is insufficient. That is, there are cases that a manager resident in the management center for managing the construction machine is absent or the number of persons sufficient to take proper measures cannot be obtained. Further, there is a case that the manager oneself cannot take full measures. Because of that, delay of measures against such a situation occurs, and there occur disadvantages in which finding of the stolen construction machine and its recovery become impossible or in which work cannot be continued at its work site.
Also, other than the theft described above, there is a case that the construction machine fails at the work site and results in being unable to operate. In such a case, a serviceman etc. are immediately sent to make repairs, or measures in which consultation from an operator of the construction machine is received, etc. are required. However, even though a system for sending information about an accident etc. from the construction machine side to a server is built, there is a case that speedy measures cannot be taken still. In addition, although it is extremely important to know the present and past operating information about the construction machine to make its repair, when an accident such as a failure of the construction machine occurs, there is a case that exact measures cannot be taken even though occurrence of a failure etc. is reported from the server to the serviceman etc.
Also, it is conceivable that a communication device provided in the construction machine is detached or destroyed. In this case, because the construction machine cannot send the position information to the server of the management center and the management center does not know whether or not the construction machine is within a work area, the management center cannot decide whether or not to stop a run of the construction machine. Even though the management center sends a run stop signal for stopping the run of the construction machine, the construction machine cannot receive its run stop signal and speedy measures against theft cannot be taken.